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Neutrinos produced in the Sun have different energies. Different types of
detectors are sensitive to different energy ranges. Image courtesy of John Bahcall, Institute of Advanced Studies

The Solar Neutrino Problem

By knowing about
fusion inside the Sun, scientists can predict the number of neutrinos
that should reach Earth. Experiments on
Earth have been set up to detect neutrinos in order to test these predictions. Right now, scientists are finding less neutrinos than predicted.

The first solar neutrino experiment was performed in South Dakota. Other experiments have been in Japan, Russia, and Italy. None of these experiments have found as many neutrinos as originally predicted.

Scientists are still trying to find out why their actual counts don't match up with the number of neutrinos that are predicted. So, if you find any extra neurinos lying around, be sure to let us know!

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